Conclusion Ferromagnetic coupling, as evidenced by the positive 9, is observed for those structures possessing... D'+ A'-D'+ A'-D'+ A'-... chains. This has also been observed for other sy~ tems.~ Of the compounds studied,[Fe (C5Me5) 2](Ni [S2C2 (CF3) 2] z) solely has an 1-D chain structure. It also has the greatest Weiss constant, 9, largest effective moment, and most pronounced field dependence of the susceptibility.[Fe (C5Me5) 2](Ni [SzC2 (CN) z] 2) ...
